Field of the Invention
The invention relates to a sensing device, and more particularly to a capacitive touch sensing device.
Description of the Related Art
A conventional capacitive touch sensing device comprises a sensing array which consists of horizontal sensing electrodes and vertical sensing electrodes. During the operation of the sensing device, the coupling of noise onto the sensing electrodes from the surrounding environment may cause errors. For example, when the sensing device is integrated with a display device, noise may be coupled onto the sensing electrodes from display electrodes of the display device. FIG. 1 shows capacitance, which is present on the sensing electrodes when the sensing electrodes are integrated on the color filter substrate of the display device. In FIG. 1, only one horizontal sensing electrode T10 and one vertical sensing electrode R10 are shown. When a grounded object 10 approaches the crossing point of the horizontal sensing electrode T10 and the vertical sensing electrode R10, the crossing capacitance Ccross between the horizontal sensing electrode T10 and the vertical sensing electrode R10 is decreased. The variation of the value of the crossing capacitance Ccross can be measured by applying a transmitting signal to the horizontal sensing electrode T10 from a transmitter 11 and by detecting the coupled signal on the vertical sensing electrode R10 using a receiver 12.
FIG. 2 shows a conventional pattern of horizontal sensing electrodes and vertical sensing electrodes in a capacitive touch sensing device. Between crossing points of horizontal sensing electrodes T1˜T3 and vertical sensing electrodes R1˜R3, these sensing electrodes are widened to firm diamond shapes. Referring to FIG. 2, all of the diamond shapes of one horizontal sensing electrode receive the same transmitting signal from a transmitter. In other words, the diamond shapes on the same horizontal row are belonged to the same horizontal sensing electrode and are not controlled independently by a transmitter, which reduces types of cross-capacitance measurement methods.